Actuating rods for brake beam retarder system



A. POLLMANN 3,114,435

ACTUATING RODS FOR BRAKE BEAM RETARDER SYSTEM 2 Sheets-Sheet 1 Dec. 17,1963 Filed Aug. 3, 1960 Inventor:-

Dec. 17, 1963 A. POLLMANN 3,114,435

ACTUATING RODS FOR BRAKE BEAM RETARDER SYSTEM 2 Sheets-Sheet 2 Fig. 4

Filed Aug- 3, 1960 1 5 42 45 43 1'2 mm 12, I I h n I36 48 13;

Jnvenfarf United States Patent i 3,114,435 ACTUATING RODS FOR BRAKE BEAMRETARDER SYSTEM Adolf Pollmann, Dinslaken, Germany, assignor to AugustThyssen-Hiitte Aktiengesellschaft, Duisburg-Hamborn, Germany Filed Aug.3, 1960, Ser. No. 48,339 Claims priority, application Germany Aug. 7,1959 6 Claims. (Cl. 18862) The present invention relates to mechanismfor actuating brake beam retarder systems associated with railroadtracks, for example in railroad shunting or marshalling yards.

The invention is characterized by a pair of rod systems extendingparallel to the line of rails and including between each other the lineof rails; these rods serve to actuate a beam retarder which generallyhas a hydraulic drive for each of the two rods. Such drives are knownfor beam retarders with actuating rollers supported on stirrups byswinging levers and actuated by springs. These rollers are linked by twopairs of rods which are parallel to the line of rails.

In the case of beam retarders it is important that differences in theretarding forces between the two wheels of a composition of wheels beavoided as completely as possible to avoid compression and torsionalstresses on the cars. The beam retarders engaging on both sides of thewheel have a very strong retarding force, and if one of the two sides ofthe retarder does not work the danger of damage exists. The inventionaims essentially at making it possible to avoid differences in theretarding :forces with simple means.

According to the invention, the two groups of rods operate in oppositionto each other; i.e. their movements are in opposite directions. The twogroups of rods are linked to each other by a compensating lever which istwo-armed and supported on a fixed pivot located below the line ofrails; in a preferred embodiment this lever is linked to the guide frameof a piston rod located below the rods (of the retarder).

The invention is based on the understanding that there can be a positiveor negative angle formed by the swinging levers of the rollers and bythe transverse plane of the line of rails; i.e. only the absolute sizeof the angle is important. Because of this all the individual partsnecessary for the actuation can be provided in pairs; only thearrangement of the parts is rotated by 180. As the compensating lever islocated lower than the rods, the invention provides straight lineguiding frames with lateral and upper connecting means for overcomingthe difference in height. This arrangement has the advantage that thehydraulic cylinders can be installed under the rods without enlargingthe overall width of the retarder.

In a preferred construction the individual bars bridging the gapsbetween two stirrups have at one end a righthanded thread and at theother end a left-handed thread. The individual bars then act asturnbuckle sleeves and allow an exact adjusting of all swinging levers.Moreover, any subsequent adjustment of the bars serving as turnbucklesreadily compensates the relatively substantial wear of the brake beamsupon first putting them in service retarder.

It also is advisable to make the roller way for each roller concavelycurved in such a way that the adjusting movement of the brake beam isproportional to the movement of the driving rods. It facilitates theadjusting of the swinging lever and makes possible a simplification forthe adjusting of the hydraulic drive.

The invention is illustrated by the construction shown in the drawing.

Patented Dec. 17, 1963 FIG. 1 shows a beam retarder in top view withportions cut away.

FIG. 2 shows the retarder of FIG. 1 in cross section along line IIII.

FIG. 3 shows the portion III of FIG. 1, enlarged, with the brake beamassociated therewith.

FIG. 4 shows diagrammatically the drawing of the curve for a roller waycorresponding to FIG. 3.

A pair of stirrups 1 is located in each substructure frame 2. Thest-irrups support brake beams 4 and 5 on both sides of the two rails 3.Numeral 6 refers to a pack of rubber, 7 an actuating roller supported bya swinging link or lever 8. The swinging links or levers 8 are connectedto rods 10 and 10' by intermediate portion 9. Parts 1 to 10 do not formpart of the invention.

The actuating rods on the two sides of the line of rails form groups ofrods 11 and 12 which correspond symmetrically to each other in allrespects and are associated with a common hydraulic cylinder 13 in themiddle of the length of the retarder. The two groups of rods 11 and 12form an adjusting pair of rods together with the cylinder associatedwith them. Cylinder 13 is fixed on a substructure frame 14 below the rod10 and has a piston 15 and a piston rod 16 which passes from oppositesides of the cylinder. The piston rod '16 is fixed at its ends to theend walls 17 of a straight line guiding frame 18 which is provided witha pair of hollow bars 19 which are slidably supported on bars 20. Thebars 20 are attached to end walls 21 which are rigid with thesubstructure frame 147 The end walls 17 of the straight line guidingframe 18 are stiffened by side walls 22 which are not shown in FIG. 1for simplicity. Hinge bolts 23 in the end walls 17 are attached toshackles 24 of the rods 19'.

A two-armed equalizing lever 26 is linked to the hollow bars 19 of thetwo straight line guiding frames 18 by two bolts 25; the lever 26 linksthe two groups of rods 11 and 12 below the line of rails and is pivotedat the center with a hinge bolt 27 on the substructure frame 1 4. Thesubstructure frame 14 is formed essentially by a pair of supportingbeams 28 linked by a cross piece 29 in the center.

The two groups of rods 11 and 12 have opposite working directions, i.e.the rods are moved in the two directions of arrows 30 and 3% for apositive application of the retarder where the gap a becomes narrowerand the brake effect is increased. The swinging levers 8 of theactuating rollers 7 are gradually pivoted towards broken line 31 aboutpins 39 when the gap a is narrowed. The equalizing lever 26 follows thefree running movement of the swinging levers 8 almost without theapplication of appreciable force, and insures the synchronism, by itsmechanical coupling, of the two groups of rods. The synchronism causesthe brake gap a, associated with both the brake beams of respective rodgroups to be equal when the wheels pass into said gaps and exert forceson the brake to cause an increase in gap a against the resistance ofrubber pack 6. Consequently, the retarding force on each of the wheelsof every set thereof is nearly the same. The equalizing lever 26 issubjected to high stresses only if there is a disturbance in theoperation of one of the two hydraulic cylinders 13 for instance. In sucha case however, the equalizing lever 26 prevents the retarder from beingoperative on only one rail, since the lever systems are constrained tomove equal amounts in opposite direction even though only one cylinder13 is operative.

In FIG. 3 the external brake beam 5 is attached by means of a screw 35onto a slide chair 36 of which only the vertical leg supporting theroller way 37 can be seen.

Between the brake beam and the leg of the chair is located a regulatingwedge 38. The intermediate portion 9 is pivotally movable about pin 39which supports link 8. The idle position of roller 7 is shown wherethere is no contact with the roller way 37.

Three gaps a a and a are shown relative to the fixably mounted brakebeam 4 in FIG. 3. The braking force is smallest at a and largest at aThe corresponding positions of the swinging lever 8 indicated by therespective center lines are shown by lines a a and a radiating from pin39.

In order to illustrate the curvature of the roller way 37, a swinginglever 8 with hinge point 39 is shown diagrammatically in FIG. 4. Numeral49 represents the roller 7 reduced to a theoretical point. Thissimplification allows the following simplified explanation: If the groupof rods is displaced in four equal increments s to the right, numeral 40passes through positions 41, 42, 43 and 44 successively and therebydescribes the circular are 45 passing through the above positions. Thestraight dotted line 46 represents the roller way according to the art.Thus if the actual dimensions of the gap a is 145 mm. in the endposition corresponding to a slight retarding effect and 125 mm. in theend position corresponding to maximum retarding, the intermediatedimensions of the gaps corresponding to the position of the link 8 arenoted on the left of FIG. 4 and clearly demonstrate that for equalangular movements of the link 8 about pivot pin 39, the gaps producedbetween the brake beam are not proportional. The ideal line is straightchain line 47, which if followed by theoretical point 40 would result inproportional adjustment of the groups of rods, according to the scaleshown on the right of FIG. 4. To obtain the ideal line 47 the dimen sionh is layed off on the line 46 as It. By laying of the distances betweenthe curve described by point 40 and the line 47 onto line 46, a curve 48is obtained. if the roller way 37 on the slide chair 35 of the brakebeam 5 is not formed as a straight line similar to 46, but as a curvesimilar to 48, the same effect is obtained as if the point 46 were tomove along the line 47. Accordingly equal displacements of rod result inequal displacements of the brake beam. Actually, the influence of thediameter of roller 7 has to be taken into account so that the actualrolling way 37 deviates slightly from curve 48.

It is understood that all the actuating points of the retarder areprovided with a roller way corresponding to curve 48. For the transitionfrom one side of the retarder to the other, the angle formed by theswinging lever 8 with respect to the transverse plane 31, is changed:from a positive to a negative angle of the same magnitude.

Only the curved rolling way 37 makes fully effective the equalization ofrods on the two sides of the retarder, because only the proportionalratio of movement makes sure that both sides of the retarder exert anequal effect on the set of wheels of the passing car.

The rods 10 and 10 are threadably engaged onto members 49 whose externalend is provided with a hinge eye for joining to intermediate part 9. Thethreads on one end of the rod It) or it) and also the pivot connectedthereto are left-handed, and at the other end right-handed. With hookkeys for insertion in the holes 59 of the rods, these rods can be turnedand have the property of a turnbuckle sleeve because the threads areopposite.

With such rods the retarder can be easily adjusted. Moreover, since thewear of the brake beam is most when the retarder is first put intoservice, it can be adjusted easily by the turnbuckle bars if theswinging levers are preset for slightly excessive wear. The deviceoperates as follows:

When it is desired to effect a braking operation on the wheels of a carpassing on the tracks, fluid is regulated in cylinders 13 by an externalcontrol means (not shown) to cause movement of pistons 15 in thecylinders. The movement of the pistons results in corresponding movementof the piston rods 16 and movement of guiding frames 18 and 18 on rods19. The movement of the frames 18 and 18 causes movement of equalizingrod 26 about pivot 27. By virtue of the location of pivot 27 midwaybetween the points of connection of the rod 26 to the frames, the framesundergo exactly equal differential displacements in opposite directions.The movement of the frames 13 and 18 causes resultant movement of therod systems 11 and 12. Each of the rod systems is constituted by rods 10and it) which are connected through portions 9 to rollers 7 which isconstrained to pivot with links 8 about pivots 39. When the rods 10 and10' are displaced, the links 8 are pivoted about pivots 39 in adirection towards or away from line 31 dependent upon the direction ofdisplacement of the rod systems. The pivots 39 are each supported on aslidable member which is in contact with rubber pack 6. The rubber packresists movement of the member supporting pivot 39 when the links 8 arepivoted by the rod systems. When the links 8 pivot about 39, they causerollers 7 to ride in roller ways 37 and cause movement of brake beams 5.By virtue of the curvature of roller ways 37, the movement of brakebeams 5 is substantially proportional to the angle through which links 8are turned.

When the wheels pass between the brake beams, a force is developedbetween the wheels and the brake beams to cause braking of the car. Theforce developed on the brake beams 5 is resisted by the roller packs 6.

I claim:

1. A brake beam retarder for applying braking forces to the wheels of avehicle passing on a parallel pair of rails, said retarder comprising: apair of rod means each parallel to a rail and displaceable in adirection substantially parallel thereto, a pair of beams adjacentopposite sides of each of the rails, means supporting at least one ofthe beams of each pair for sliding movement transverse of the associatedrail, means connecting each of the rod means to a corresponding one ofsaid pair of beams to cause movement of the latter relative to theassociated rail in an amount which is proportional to movement of therod means, hydraulic means coupled to each of the rod means fordisplacing the same, and an equalizing lever operatively associated withthe hydraulic means of each rod means to cause equal movement of each ofthe rod means in opposite directions.

2. A retarder as claimed in claim 1 wherein the means connecting each ofthe rod means to a corresponding one of the brake beams, comprises apivotally supported link connected to the associated rod means, forundergoing pivotal movement in response to movement of the rod means, aroller supported on said link for movement therewith, a roller waysupported on said one brake beam and moveable therewith, said rollerbeing in contact with said roller way for causing displacement of thelatter and the said one brake beam therewith upon pivotal movement ofthe link, said roller way being of arcuate shape to provide displacementof the associated one brake beam which is proportional to displacementof said rod means.

3. A retarder as claimed in claim 1 wherein the hydraulic meanscomprises a cylinder and a piston in the cylinder, said retardercomprising a frame for each of the hydraulic means which is supportedfor sliding movement substantially parallel to said rails under theaction of an associated piston of the hydraulic means, said equalizinglever being connected to each of said frames to cause correspondingmovements thereof in opposite directions.

4. A retarder as claimed in claim 3 comprising means connecting each ofthe rod means to a respective one of the frames whereby the rods aredisplaced in accordance with movement of the frames.

5. A retarder as claimed in claim 1 wherein the rod means comprises aplurality of interconnected rods and an intermediate portion connectedto the links associated with each of said one brake beams, and connectedto rods of the rod means, each intermediate port-ion including ends ofopposite threading in threaded engagement with associated rods therebyenabling relative adjustment of the latter.

6. In a brake beam retarder adapted for applying braking forces to thewheels of a vehicle adapted for passing on a parallel pair of rails, theretarder being of the type having a brake beam associated with each railand supported for movement in a direction transverse thereto, a rodsystem for each rail associated with said brake beam for controlling theposition thereof relative to said rail and a hydraulic device for eachrod system for moving the same to in turn cause movement of therespective brake beams relative to the rail associated therewith, animprovement for the retarder comprising: an equalizing lever, meanspivotally supporting the equalizing lever midway thereof, meansconnecting each of the hydraulic devices to the equalizing lever atlocations on the latter substantially equidistant from the pivotalsupport of the 6 lever, means connecting each of the rod systems to thelast said means to cause synchronized, equal movement of the rod systemsin opposite direction under the action of said equalizing lever and thehydraulic device, and

means connecting each of the rod systems with a respective brake beam tocause movement of the latter relative to the associated rail in anamount which is proportional to movement of the rod systems.

References Cited in the file of this patent UNITED STATES PATENTS1,280,873 Schuh Oct. 8, 1918 1,459,574 Cover et al June 19, 19231,629,286 McCallum May 17, 1927 1,871,929 Varble et al. Aug. 16, 19321,907,037 Bickley May 2, 1933 2,679,809 Beltman June 1, 1954 2,943,709Schode July 5, 1960 FOREIGN PATENTS 733,207 Great Brita-in July 6, 1955947,172 Germany Aug. 9, 1956

1. A BRAKE BEAM RETARDER FOR APPLYING BRAKING FORCES TO THE WHEELS OF AVEHICLE PASSING ON A PARALLEL PAIR OF RAILS, SAID RETARDER COMPRISING: APAIR OF ROD MEANS EACH PARALLEL TO A RAIL AND DISPLACEABLE IN ADIRECTION SUBSTANTIALLY PARALLEL THERETO, A PAIR OF BEAMS ADJACENTOPPOSITE SIDES OF EACH OF THE RAILS, MEANS SUPPORTING AT LEAST ONE OFTHE BEAMS OF EACH PAIR FOR SLIDING MOVEMENT TRANSVERSE OF THE ASSOCIATEDRAIL, MEANS CONNECTING EACH OF THE ROD MEANS TO A CORRESPONDING ONE OFSAID PAIR OF BEAMS TO CAUSE MOVEMENT OF THE LATTER RELATIVE TO THEASSOCIATED RAIL IN AN AMOUNT WHICH IS PROPORTIONAL TO MOVEMENT OF THEROD MEANS, HYDRAULIC MEANS COUPLED TO EACH OF THE ROD MEANS FORDISPLACING THE SAME, AND AN EQUALIZING LEVER OPERATIVELY ASSOCIATED WITHTHE HYDRAULIC MEANS OF EACH ROD MEANS TO CAUSE EQUAL MOVEMENT OF EACH OFTHE ROD MEANS IN OPPOSITE DIRECTIONS.